package com.atguigu.gulimall.cart.interceptor;

import com.atguigu.common.constant.AuthServerConstant;
import com.atguigu.common.constant.CartConstant;
import com.atguigu.common.vo.MemberRespVo;
import com.atguigu.gulimall.cart.vo.UserInfoTo;
import org.apache.commons.lang.StringUtils;
import org.springframework.lang.Nullable;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.util.UUID;

/**
 *在执行目标方法之前，判断用户的登录状态。并封装传递给controller目标请求
 *
 **/
@Component
public class CartInterceptor implements HandlerInterceptor {

	public static ThreadLocal<UserInfoTo> threadLocal = new ThreadLocal<>();

	@Override
	public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
			throws Exception {
		UserInfoTo userInfoTo = new UserInfoTo();
		//正常用户信息存放至session
		HttpSession session = request.getSession();
		MemberRespVo member = (MemberRespVo) session.getAttribute(AuthServerConstant.LOGIN_USER);
		if (member !=null){
			//用户登录
			userInfoTo.setUserId(member.getId());
		}
		Cookie[] cookies = request.getCookies();
		//临时用户信息存放至cookie
		if (cookies!=null && cookies.length>0){
			for (Cookie cookie : cookies) {
				//user-key
				String name = cookie.getName();
				if (name.equals(CartConstant.TMP_USER_COOKIE_NAME)){
					userInfoTo.setUserKey(cookie.getValue());
					userInfoTo.setTempUser(true);
				}
			}
			//如果没有临时用户,创建一个user-key
			if (!StringUtils.isEmpty(userInfoTo.getUserKey())){
				String uuid = UUID.randomUUID().toString().replace("-","");
				userInfoTo.setUserKey(uuid);
			}
		}
		//目标方法执行之前
		threadLocal.set(userInfoTo);
		return true;
	}

	/**
	 * 业务执行之后,分配临时用户，让浏览器保存
	 */
	@Override
	public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, @Nullable ModelAndView modelAndView) throws Exception {

		UserInfoTo userInfoTo = threadLocal.get();

		if (!userInfoTo.isTempUser()){
			Cookie cookie = new Cookie(CartConstant.TMP_USER_COOKIE_NAME, userInfoTo.getUserKey());
			cookie.setDomain("gulimall.com");
			cookie.setMaxAge(CartConstant.TMP_USER_COOKIE_TIMEOUT);
			response.addCookie(cookie);
		}
	}
}
